The oil pressure seems to be getting lower and lower when running at 3000 rpm.

 

When started from cold at idle the pressure is steady at about 90 psi which then slowley drops to 30 psi as the engine warms up.

 

Under driving conditions once the temeparture guage get to the fully warmed position the oil pressure is at about 65 psi with 3000 rpm but over the next say 10-15 miles this drops to about 40 psi. If you accelerate hard this gets up to about 50 psi then drops back down.

 

Any ideas. She used to be rock steady at 60-65 psi under these conditions. The oil pressure sender is new and the previous one behaved the same way.

i would check it with an oil pressure test gauge, which screws directly into the sender hole. far more accurate way of testing oil pressure.